This oversight led to a massive memory leak — upwards of 10KB per tuple
— during creation-time verification of an exclusion constraint based on a
GIST index. In most other scenarios it’d just be a leak of 10KB that would
be recovered at end of query, so not too significant; though perhaps the
leak would be noticeable in a situation where a GIST index was being used
in a nestloop inner indexscan. In any case, it’s a real leak of long
standing, so patch all supported branches. Per report from Harald Fuchs.

There were a few fixes for catalog or catalog index corruption, and avoidance of buffer overflows which could cause a backend crash. There were also a few fixes that will improve the performance of VACUUM over time.

Release notes have all the details. Many of the fixes have already been committed to 9.1 (there are only 11 new commits in 9.1.1). So, you’re about to experience a great many bugfixes, users of 8.2->9.0.

Another thing to note – 8.2 will be deprecated in 2011! You ought to upgrade anyway, just to get HOT and to get yourself into a position to use pg_upgrade for future upgrades. But now, you’ve got extra incentive.